1. Field of the Invention
The present invention relates to an apparatus for recording and reading binary information on a magnetic disc having a plurality of concentric recording tracks, means for rotating the magnetic disc, at least one magnetic head for recording and reading information on magnetic head radially with respect to the disc to position it on a selected recording track, and a voltage source for supplying the stepping motor.
A first object of the present invention is to increase the dynamic torque of the stepping motor so as to obtain a reduction in the time necessary for positioning the magnetic head with respect to the selected track, and consequently a reduction in the time of access to the recorded information.
2. Description of the prior art
An apparatus is known in which a voltage multiplier is interposed between the voltage source and the stepping motor and is synchronized with the timing pulses which control the phases of the motor itself, in order to obtain at the beginning of each energization of the motor windings an energizing voltage which is a multiple of that supplied by the voltage source. This apparatus, however, has the drawback of obtaining increments of the energizing voltage which are not constant, but only pulsed and linked to the frequency of the command pulses of the phases of the motor.